This invention relates to a method for manufacturing multiple push-button and conductive members for dual-in-line package (DIP) switches, and particularly to that method by which the multiple push-button and conductive members are integrally produced and simultaneously processed to provide individual push-button units which are free from any burs so as to assure the precision of DIP switches.
it is known that the DIP switch is an indispensable item in the development of the information industry because all DIP switches are directly installed on PC boards to effect various functional settings usually concerning arithmatic operations with the digits "0" and "1". It is for this reason that the structure of the DIP switches must be of high quality and precision, so as to ensure the exactness of the signal output therefrom. Unfortunately, the known method for producing the push-button and conductive members of the conventional DIP switches cannot satisfy the high precision requirement. As shown in FIG. 1, the structure of the conventional DIP switches is generally composed of a substrate 1, a plurality of leads 2 extending from two opposing sides of the substrate 1, a plurality of push-button members 3 and a cover 4. The substrate 1 is provided with a rectangular open section 1a for accommodating the push-button members 3. Each of the push-button members 3 is composed of a push button 3a having an upper pushing post 3a1 extending upward in the middle and a lower pushing post 3a2 protruding downward from the bottom side of the upper push post 3a1, and a conductive member 3b superimposedly disposed on the bottom side of the push button 3a with the lower pushing post 3a2 being inserted into an opening 3b1 of the conductive member 3b. Such a delicately combined article should be produced with high quality for satisfying the high precision requirement. Unfortunately, the known method for manufacturing the push-button member 3 normally consists the following steps: separately molding each push button 3a and each conductive member 3b in a respective mold; removing the molded push button 3a and the conductive member 3b from the respective mold with a driving rod; and separately combining each conductive member 3b with each push button 3a to form a push-button unit 30. The individually combined push-button units 30 are then respectively arranged within the open section 1a of the substrate 1 with the cover 4 having a plurality of openings 4a formed therein being connected to the substrate 1 with each upper pushing post 3a1 protruding out of the respective openings 4a. The shortcomings of the combined push-button units 30 produced by the above known method are as follows:
(1) All the push buttons 3a are made of a plastic material and are generally produced through injection molding. It is well known that, during injection operation, when the movable mold portion is open, and the molded part is to be ejected from the mold cavity, a push rod is usually used to drive the molded part out of the mold cavity. Owing to the fact that during the ejection period, the push rod and the mold are both being maintained at a high temperature, and that since a slit usually exists in the stationary mold portion for permitting the push rod to move therein so as to thrust the molded part out of the cavity of the stationary mold, a plurality of driving marks thus made by the push rod are always left on the molded part. These marks are normally called "burred ridge" or "burs", and these "burs" will increase with every operation of the mold. As a structure of a DIP switch is usually very small, the burs left on the smaller push-button members 3 will certainly affect the precision of their performance.
(2) The manufacturing operations and combination of all the push buttons 3a and the conductive members 3b are usually manually carried out one item at a time. This kind of working is rather time-consuming and wastes too much manpower.